wcf data services (i.e. astoria) is great. It is a nice way to expose your data and service methods.  There are some limitations in how you can query.  For example, you can't do a select many (e.g. for-for). So it not like have a full query connection.  But normally you can work around those cases by creative query or going other way in the relation.  With built-in support from clients like Excel (et all) and LinqPad, it is a good thing.  Using LinqPad for dev and test is a real time saver and just a good ad-hoc tool.   You can also self host the .srv (if you need tight control or startup or shared state) in addition to using IIS hosting and can use plain old CLR objects in additon to DB, so there is a lot options that get surfaced in uniform way.  Facebook insights uses it. http://www.odata.org/producers